[PATCH v3 25/35] x86/bugs: Add attack vector controls for rfds

David Kaplan
2025-01-08T20:25:53Z

Use attack vector controls to determine if rfds mitigation is required.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
arch/x86/kernel/cpu/bugs.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 4249a1f1524c..d9b12c706fc0 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -783,8 +783,12 @@ static void __init rfds_select_mitigation(void)
if (rfds_mitigation == RFDS_MITIGATION_OFF)
return;

- if (rfds_mitigation == RFDS_MITIGATION_AUTO)
- rfds_mitigation = RFDS_MITIGATION_VERW;
+ if (rfds_mitigation == RFDS_MITIGATION_AUTO) {
+ if (should_mitigate_vuln(X86_BUG_RFDS))
+ rfds_mitigation = RFDS_MITIGATION_VERW;
+ else
+ rfds_mitigation = RFDS_MITIGATION_OFF;
+ }
}

static void __init rfds_update_mitigation(void)
--
2.34.1